Agent for keeping cut flowers fresh

ABSTRACT

AGENT FOR KEEPING CUT FLOWERS OR OTHER PLANT PARTS FRESH WHICH CONTAINS, IN ADDITION TO CONVENTIONAL INGREDIENTS, A CHLOROCHOLINE SALT, CITRIC ACID, A SILVER SALT AND A SALT OF N-NITROSO-N-CYCLOHEXYLHYDROXYLAMINE, AND A PROCESS FOR KEEPING CUT FLOWERS FRESH WITH THIS AGENT.

United States Patent 3,826,639 AGENT FOR KEEPING CUT FLOWERS FRESH Ernst-Heinrich Pommer, Limburgerhof, and Hannelore Will, Ludwigshafen, Germany, assignors to Badische Anilin- 8: Soda-Fabrik Alttiengesellschaft, Ludwigshafen (Rhine), Germany No Drawing. Filed Feb. 4, 1972, Ser. No. 223,758

Int. Cl. A01n 3/02 US. Cl. 7168 Claims ABSTRACT OF THE DISCLOSURE Agent for keeping cut flowers or other plant parts fresh which contains, in addition to conventional ingredients, a chlorocholine salt, citric acid, a silver salt and a salt of N-nitroso-N-cyclohexylhydroxylamine, and a process for keeping cut flowers fresh with this agent.

The present invention relates to an agent for keeping cut flowers or other plant parts fresh which contains a chlorocholine salt, citric acid, a silver salt and a salt of N-nitroso-N-cyclohexylhydroxylamine.

It is known to preserve the freshness of cut flowers by adding a preservative to the water in which the flowers stand. Such mixtures contain for instance a mixture of sugar and sugar derivatives, a pH stabilizer, e.g., an organic carboxylic acid having a low molecular weight, and a microbicide (German Printed Application DOS 1,542,- 832). However the action of these conventional agents is unsatisfactory.

We have now found that the disadvantages of these known agents may be avoided if they contain a chlorocholine salt, citric acid, a silver salt and a salt of N- nitroso-N-cyclohexylhydroxylamine. By chlorocholine salts, we means quite generally salts of chlorocholine (N-trimethyl N 2-chloroethylammonium salts) with acids, e.g., hydrochloric acid, hydrobrornic acid, sulfuric acid, phosphoric acetic acid and propionic acid. Cholorocholine chloride is preferred because it is easily accessible and is already used in large amounts in agriculture.

By silver salts we mean generally the water-soluble salts of silver with inorganic or organic acids, e.g., nitric acid and acetic acid. Silver nitrate is preferred because it is easily accessible industrially.

By salts of N-nitroso-N-cyclohexylhydroxylamine" we mean generally the alkali metal and alkaline earth metal salts. It is preferred to use the sodium salt, the calcium salt or mixtures of these two salts.

The process according to the invention for preserving cut flowers consists in adding the abovementioned preservative to the water in which the cut flowers stand and finely distributing it therein. An aqueous solution is obtained in which the freshness of cut flowers is preserved over a long period of time.

The good action of the preservatives according to the invention is attributable to the presence of chlorocholine salts, citric acid, a silver salts and a salt of N-nitroso- N-cyclohexylhydroxylamine; the chlorocholine salts are used in an amount of from 0.012 to 0.004% by weight; citric acid in amount of from 0.06 to 0.02% by weight; the silver salt in an amount of from 0.00024 to 0.00008% by weight; and the salt of N-nitroso-N-cyclohexylhydroxylamine in an amount of from 0.003 to 0.001% by weight, with reference to the water in which the cut flowers stand. The agents according to the invention also contain substances which are contained in conventional preservatives, e.g., sugar or sugar derivatives, particularly cane sugar and dextrose, and which are used in amounts, with reference to the water in which the flowers stand, of from 1 to 3% by weight. The agents according to the invention may additionally contain microbicidal compounds, e.g., N-alkyl (alkyl radical of 12 to 14 carbon atoms) -N,N-dimethyl-N-benzylammonium chloride, 1,3- bis (p-isobutylbenzyl)-imidazolium chloride, phenylmercuric acetate, Agri-mycin, potassium sorbate and mixtures of these compounds, in amounts of from 0.02 to 0.0001% by weight with reference to the water in which the cut flowers stand. By adding the preservative to the water in which the flowers stand and finely dispersing it therein an aqueous solution is obtained which prevents premature wilting of the flowers. The agent according to the invention itself contains the individual substances in concentrated form and is converted into the aqueous solution which preserves the cut flowers by dilution with Water, approximately in the ratio of concentrate to water of from 1:20 to 1:50 parts by weight. The following compositions demonstrate the abovementioned advantageous properties.

Concentration in Wt Compopercent in sition Components the water 1 Cane sugar 1. 5 Citric acid 0. 03 Chloroethyltrimethylammoninm chloride 0. 006 N-nilgroso-N-cyclohexy1hydroxylamine, sodium 0. 0015 sa Silver nitrate 0. 00012 2 Cane sugar 1. 5 Citric acid H. 0. 03 Cliloroethyltrimethylammonium chloride. 0. 006 N-nitrcso-N-cyclchexylhydroxylamine, calci- 0.0015

um salt. Silver nitrate 0.00012 3 Cane sugar 1. 5 Citric acid 0. 03 Chloroethyltrimethylarnmoninm chloride. 0.006 N-nitroso-N-cyclohexylhydroxylarnine, sodi- 0. 001

um salt.

N-nitroso-N-cyclohexylhydroxylamine, calci- 0.001

um salt.

Silver nitrate 0. 00012 4 Glucose 2. 0 Citric acid 0.02 Chlorocholine chlorid 0. 004. N-nitroso-N-cyclohexylhydroxylami e, sodi- 0.0015

um salt.

N-nitroso-N-cyclohexylhyd.roxylamine, calci- 0. 0015 um salt.

Silver nitrate 0 00012 5 Cane sugar 1. 0 Citric acid 0.03 Chlorocholine chloride O. 006 N-nitros0-N-cyc1ohexylhydroxy1amine, calci- 0.0015

um salt. Silver nitrate 0.00012 6 Cane sugar- 3 0 Citric acid 0. 04 Chlorocholine chlorid 0.012 N nitroso-N-cyclohexylhydroxy1amine, calci- 0. 0015 um salt. Silver nitrate 0. 00024 7 Cane sugar 1. 5 Citric acid 0. 03 Chlorocholine chloride 0. 004 N-nitr0so-N-cyclohexylhydroxylamine, sodi- 0. 003

um salt. Silver nitrate 0. 00008 8 Cane sugar 1. 5 Citric acid 0. 03 Chloroclioline chloride 0. 005 N-nitroso-N-cycloliexylhydroxylamine, sodi- 0. 0015 um salt. Silver nitrate 0. 00008 1,3:lais-(p-isobutylbenzyl)-imidazolium chlo- 0. 002

9 Glucose 1. 0 Citric acid 0.06 Chlorocholine chloride 0. 008 N-m'trOSO-N-cyclohexylhydroxylamine, sodi- 0.001

um salt. Silver nitrate 0. 00012 TABLE-Continued Concentration in wt. Compopercent in sition Components the water 10 Glucose 1. 5 Citric acid 0. 04 Chlorocholine chloride O. 004 N-nitroso-N-cyclohexylhydroxylamine, sodi- 0. 003

um salt. Silver nitrate 0. 00016 Cane sugar 2.0 1. Citric acid 0.03 Chlorocholine chloride 0. 004 N-nitroso-N-cyclohexylhydroxylamine, sodi- 0. 0015 um salt. Silver nitrate 0. 00012 12 Cane sugar 1. Citric acid 0.02 Chlorocholine chloride 0. 004 N-nitroS0-N-cyclohexylhydroxylainine, sodi 0. 0015 um salt. Silver acetate 0. 00012 The good preservative properties of the compositions according to the invention are illustrated in the following examples.

EXAMPLE 1 cut greenhouse carnations are placed, at to 22 C., in glass vessels containing 500 ml. of water in which the substances listed in the compositions have been dissolved before commencement of the experiment. As controls, there are used tap water and a mixture of cane sugar, citric acid and alkyldimethylbenzylammonium chloride. After 8 and 14 days the carnations which are still fresh are counted.

EXAMPLE 2 The procedure of Example 1 is adopted with the exception that 10 cut roses of the Super Star variety are used. The number of fresh roses is determined after 2, 4, and 5 days.

Number of fresh roses after 2 days 4 days 5 days Composition:

10 9 9 10 9 9 10 8 7 10 10 8 age cane sugar 1.35%; citric acid 0.15%; N-alkyl-N,N-dimethylbenzylammonium chloride 0.01% 10 2 0 Tap water (control) 6 O 0 We claim:

1. A composition for preserving the freshness of a cut flower which comprises:

(a) 4 to 12 parts by weight of the chlorocholine salt of an acid selected from the group consisting of hydrochloric acid, hydrobromic acid, sulfuric acid, phosphoric acid, acetic acid and propionic acid;

(b) 20 to 60 parts by weight of citric acid;

(0) 0.08 to 0.24 parts by weight of a silver nitrate;

(d) 1 to 3 parts by weight of a compound selected from the class consisting of the alkali metal and alkaline earth metal salts of N-nitroso-N-cyclohexylhydroxylamine; and

(e) 1,000 to 3,000 parts by Weight of a sugar.

2. A composition as claimed in Claim 1 wherein component (a) is chlorocholine chloride.

3. A composition as claimed in Claim 1 containing as component (f) at least 0.1 parts by weight of a microbiocidal compound which is selected from the class consisting of N-alkyl-N,N-dimethy1-N-benzylammonium chloride of 12 to 14 carbon atoms in the alkyl radical, 1,3-bis- (p-iso'butylbenzyl)-imidazolium chloride, phenylmercuric acetate, Agri-mycin, potassium sorbate and mixtures thereof.

4. A composition as claimed in Claim 1 wherein component (d) is selected from the class consisting of the sodium and calcium salts of said N-nitroso-Ncyclohexylhydroxylarnine and mixtures thereof.

5. A composition as claimed in Claim 1 dissolved as a concentrate in about 2,000 to 5,000 parts by weight of water.

6. A composition as claimed in Claim 5 diluted with water in a ratio of 1:20 to 1:50 parts by weight.

7. A process for preserving the freshness of a cut flower which comprises placing the cut flower in an aqueone solution in which there is dissolved with reference to the water:

(a) 0.004 to 0.012% by wt. of a chlorocholine salt;

(b) 0.02 to 0.06% by wt. of a citric acid;

(0) 0.00008 to 0.00024% by wt. of a watersoluble silver salt;

(d) 0.001 to 0.003% by wt. of a compound selected from the class consisting of the alkali metal and alkaline earth metal salts of N-nitroso-N-cyclohexyihydroxylamine;

(e) 1 to 3% by wt. of a sugar; and

(f) 0 to 0.02% by wt. of a microbiocidal compound.

8. A process as claimed in Claim 7 wherein component (a) is chlorocholine chloride.

9. A process as claimed in Claim 8 wherein component (d) is a compound selected from the class consisting of the sodium and calcium salts of N-nitroso-N-cyclohexylhydroxylamine and mixtures thereof.

10. A process as claimed in Claim 9 wherein component (c) is silver nitrate.

References Cited UNITED STATES PATENTS 2,805,137 9/1957 Clopton 71-68 2,923,094 2/1960 Ryan 7l78 3,395,009 7/1968 Oettel 71121 FOREIGN PATENTS 1,088,681 3/1955 France 71121 JAMES O. THOMAS, JR., Primary Examiner UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION PATENT NO. I 3,826,639 DATED July 30, 1974 'NVENTOR(5) 1 Ernst-Heinrich Pommer et al.

It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

. In Column 1, after Line 7, insert "Claims priority,

application Germany, February 16, 1971, P 21 07 298.0"

In Column '1, Line 38, delete "phosphoric acetic acid" and substitute -phosphoric acid, acetic acid...-

In Column 2, Line 3, delete "bis(pisobutylbenzyl)" and substitute bis-(p-isobutylbenzyl)- Signed and Scaled this twenty-second Day Of June 1976 [SEAL] Arrest:

RUTH c. MASON a c. MARSHALL DANN Arresting Officer Commissioner of Patents and Trademark; 

